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arXiv · 1008.1874

Quasi-freestanding and single-atom thick layer of hexagonal boron nitride as a substrate for graphene synthesis

D. Usachov·D. Haberer·A. Grüneis·H. Sachdev·A. B. Preobrajenski·V. K. Adamchuk·C. Laubschat·D. V. Vyalikh
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Abstract

We demonstrate that freeing a single-atom thick layer of hexagonal boron nitride (hbn) from tight chemical bonding to a Ni(111) thin film grown on a W(110) substrate can be achieved by intercalation of Au atoms into the interface. This process has been systematically investigated using angle-resolved photoemission spectroscopy, X-ray photoemission and absorption techniques. It has been demonstrated that the transition of the hbn layer from the "rigid" into the "quasi-freestanding" state is accompanied by a change of its lattice constant. Using chemical vapor deposition, graphene has been successfully synthesized on the insulating, quasi-freestanding hbn monolayer. We anticipate that the in situ synthesized weakly interacting graphene/hbn double layered system could be further developed for technological applications and may provide perspectives for further inquiry into the unusual electronic properties of graphene.

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D. Usachov, D. Haberer, A. Grüneis, H. Sachdev, A. B. Preobrajenski, V. K. Adamchuk, C. Laubschat, D. V. Vyalikh. 2010-08-11. Quasi-freestanding and single-atom thick layer of hexagonal boron nitride as a substrate for graphene synthesis. https://doi.org/10.1103/physrevb.82.075415

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